The basic machinery
(heating element, solenoid valves, thermistor, silicone tubing, tank gasket) are the same as from
a Curtis coffee brewer, but pretty much everything else was made from
scratch from copper and stainless steel.

I have been
developing this project for a local coffee house.

It's a microcontroller controlled 3 station pour-over machine. It times
out hot water in 2 doses with a pause in between to drip down.One of the dump
valves with the RGB LED (ws2801 from sparkfun) controller above it.

This is the Sanguino Microcontroller (similar to an Arduino but with
more pins) that keeps the tank full, regulates water temperature, times
out the doses of hot water, and keeps the colors of the buttons
updated. I use the cheap parallel displays, so they use 7 pins from the
microcontroller.

I design my circuit boards with a pen and paper, scan them, clean them up, and print them out with a laser printer.

The Warning labels were also etched with toner transfer method.

for temperature control, I am using a thermistor and a solid state
relay (no PID at the moment, but it really isn't needed for this simple
job). The 4 valves are controlled by optocoupler controlled BTA-10
triacs. Tank level sensing is done with a probe that sticks into the
tank through a teflon bushing, a resistor (28K), a small 100pf cap, an
assert pin, and a sense pin.

Art circuit board. Made with the toner transfer method.

The buttons are made from fiberglass and epoxy resin laid up in crude clay
open face molds. They contact microswitches to get the message to the
microcontroller. The program is based on sample intervals with a stage
counter, so that takes care of de-bouncing.

I'm cleaning up the code and commenting it, and will post it here.

Here it is at work at TH Benton's Coffee / Deli in Bentonville, AR.
So far, so good. I plugged it in to the laptop for a slight software upgrade today.